PhD Studentships: Sensory Ecology, Parasites and Mate Choice in the Guppy, POECILIA RETICULATA

Jessica Stephenson

Cardiff University & Bristol University

Supervisor(s): Joanna Cable & Gabrielle Archard, & Julian Partridge

My research focuses on the way information from different sensory systems (vision and olfaction) interact to inform animal decisions. I am using the guppy-gyrodactylid model system to test how parasitism affects this interaction in a mate choice context. In dissecting the mechanism by which parasitism can alter mate choice in this host, the project will increase understanding of how sexual selection changes in parasitized populations. Furthermore, this could provide an explanation for the maintenance of anomalously high Major Histocompatibility Complex (MHC) allelic diversity in parasitized fish populations.

How an individual’s mate choice preferences change over time is an understudied area of evolutionary ecology. Condition-dependent variation in mate choice preferences between individual female guppies has been demonstrated. It is likely, though little tested, that there is also within-individual variation in preference because condition will change through time. One mechanism by which preferences may vary both between and within individuals is through alteration in the rank females attribute to each of the several cues used during mate choice. These cues in guppies have been well studied; in healthy females mate choice appears to be based largely on visual cues, females prefer males with intense carotenoid colouration and high display rate. The role of olfaction in guppy mate choice has received little attention and is uncertain, though it is through olfaction that animals (including fish) assess MHC compatibility. Susceptibility to parasites is linked to MHC genotype in guppies, so choosing mates based on MHC compatibility is likely to increase guppy reproductive fitness. Olfactory cues may also serve to ‘prime’ the visual system, as has been found in zebrafish. I am using a range of behavioural experiments to test hypotheses relating to condition dependent, within individual variation in the use of information from different sensory modalities in a mate choice context.


Cardiff School of Biosciences,
Biomedical Sciences Building,
Museum Avenue,
CF10 3AX